4.
The sales record of a real estate agency show the following sales over the past 200 days.

Number of Number
Houses Sold of Days
0 60
1 80
2 40
3 16
4 4
200
a. How many sample points are there?
5

b. Assign probabilities to the sample points and show their values.
60/200 = 0.3
80/200 = 0.4
40/200 = 0.2
16/200 = 0.08
4/200 = 0.02
1
c. What is the probability that the agency will not sell any houses in a given day?
60/200 = 0.3

d. What is the probability of selling at least 2 houses?
60/200 = 0.3

e. What is the probability of selling 1 or 2 houses?
80+40 = 120/200 = 0.6

f. What is the probability of selling less than 3 houses?
16+40+80+60 = 196/200 = 0.98

5.
Six viamin and three sugar tablets identical in appearance are in a box. One tablet is taken at random and given to person A.
A tablet is then selected and given to Person B.

7.
a. Define the random variable in words.
A random variable is a numerical description of the outcome of an experiment. The particular numerical value of the random variable depends on the
outcome of the experiment. In this case we have a discrete random variable.